Chapter 2. Prehension

Chapter 6 - During Contact 267
6.6 Moving a Grasped Object: Transporting,
Twiddling, and Twirling
In this section, we focus on the subgoals of holding,
transporting, manipulating and placing, considering experimental and
analytic approaches.
6.6.1 Manipulation by humans
In acquiring an object into stable grasp, the system being
controlled changes from the hand to the hand plus object. The object
becomes an extension of the hand (Polanyi, 1958), and the new
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Frequency (Hz)
Figure 6.21 Distribution of temporal frequencies obtained for
active touch, or exploratory tasks (tactile discrimination of ball
and cube shapes, or plastic and sandpaper textures) are clustered
from 1 - 2 Hz, whereas the frequencies for performatory
movements like (writing, tapping and shading) cluster from 4 - 7
Hz. The role of sensory information in motor control is
fundamentally different for exploratory and performatory
movements, consistent with the work of Gibson (1962) and
Lederman and Klatzky (1987). (from Kunesch, Binkofski and
Freund (1989); reprinted by permission).